Beznau nuclear power plant: Unit 1 begins overhaul

13.03.2026 – Today, the overhaul of Unit 1 at the Beznau nuclear power plant (KKB) begins. The main focus of the overhaul includes axpo maintenance work, recurring tests and inspections. The revision will last approximately ten weeks.

Since the start of the current operating cycle on April 24, 2025, Unit 1 has produced approximately 3 billion kilowatt-hours of electricity – equivalent to the average annual consumption of around 650,000 four-person households.

During the shutdown of the reactor, steam may be visible above the machine house (non-nuclear part). This steam is harmless and poses no risk to people or the environment. The overhaul is supervised by the Swiss Federal Nuclear Safety Inspectorate (ENSI).

The KKB reliably and safely generates around 6 terawatt-hours of electricity per year, covering approximately one-tenth of Switzerland's electricity demand. Both reactor units are taken offline in the spring/summer for fuel element replacement or revision. Afterward, they again provide their important contribution to Switzerland's energy security for around one year – particularly during the winter months.